Method of manufacturing radially corrugated disks



March 9, 1937.A 1D. BQLESKY 2,072,847

Patented Mar. .9,1'f1937i 2,012,841 oF MANUFacTUnmG miams coanUGA'rl-:D nrsxs 'John' 1'). Bolesky, lAttleboro, Mass., assigner, by

mesne assignments. to

Metals `Controls Corporation. AttleboropMass., a corporation Massachusetts Application November turing radially corrugated disks, and withregard 'illust'ated one of various possibletion;

to certain morel s'pcic features, to'methods adapted to commence with uncorrugated blanks. 'Ihis invention is an improvement on the in- 'vefntion shown and describeddn John A. Spencer Patent No. 2,001,553, dated Mayu, 1935.

The product obtainedl by' carrying out the method oi the present. invention is described and claimed in John A. spencer Patent Nos. 1,895,590

and ,$95,591. bamdated January 31; 1933.

' ong the several objects of the invention may be noted the provision' o f a'method of manufacturing radiallyA orrugated disks. which commences with .an corrugated disk-shaped blank oi either resilientodinary metal or composite thermcstatic metal (such as bimetalr; and produces snap-acting disks which are thermostatically sensitive if composite metal has been used; a method of the class described which achieves the desired ultimate conformation wlthoutin'the.

"course of theV method subjecting the blanks to sny undue localized stresses which'might.

impair i the eiiiciency o! the" resulting article; the prov'isioii .oi' a'method of the class describedwhich is independent ofjthe use of Vrollers, and .thereby eliminates the diiliculties inherent in Vsuitably diadnumber'of corrugations; and the provision of a method ofthe class described which is simple and 'economical "in'operation, requiringbut' a minimulnof specialized machinery: Other jects will be in .part .obvious and 'out hereinafter. .The invention accordingly comprises the steps and sequence of s teps, and features of operation.

in part pointed which will bevexemplld in the methodsherematter described. and the scpe' or tne'appiication of which will bein'dicad in th following YIn the accoxipanying which isgof the invention.- f .i

suman; a mank utilized in the present inven- Flg: 2 is anV elevation oithe .il'skoiI 1'; l

Fig. 3- is'a plan view ofthe disk of Fig. r-aiter an initiall operation has been performed thereon;

4 is an elevation oi' the disk in its Fig. 3 condition;v

5 is a topplan view of the disk of Fig.V 3 after a second operation;

Fig. 6 is an elevation of the disk in its Fig. 5 condition;

einbodiments A circular blank, in the form oa disk, corrugating' Tig. 1 is a plan/tiew of a circiilar disk, coni that it is brought to .a cup-shape, die-cutting the 46 2z, 1935, sei-iai N. '51,o35 5 ciai'ms. (ci. 15a-2i Flg. .7 is a vertical cross sectionl taken substantially along lines 1.-1 oi Fig. 5;;

Fig. 8 is a top planview of the' disk of Fig. 5 v .aitera subsequent operation;

Fig. 9 is a'plan-view ofone snap-acting disk;

- Fig. lois a plan` view of a second form of ished snap-acting disk; and,

Fig.- 11 is a cross'section .taken .substantially along line ll-ll of 10.

Similar reference characters indicate .corfrespondirig partst'hroughout the several views of `the drawings.' -As disclosedI in the said John Spencer Patients Nos. 1,895,590 and 1,895,591, radla1ly corrul5 gated disks ng a slight iriitialv conical cori,- formation., when'made of suitable rnaterial, are useful as snap-acting elements. vIf the material is resilient fsheet metal, the disk constitutes -a ferm 'of @mashed s snap-acting unit. The present application is not '25 y concerned with Ithe actions and reactions of these disks perse, which are adequately. discussed in mensicning rollers to produce the desired shape said patents. but in a preferred method (or meth'- ods) `of,manu i acturing the same. Thei'nethod used, particula-rly if the -disks are-. tliermostatic .-80 ones needs to` be such that no excessive localized stresses. are produced in .any one region of tha fdisk.. Otherwisethe temperature i'gesponsivg:

characteristics of the disk might be seriously imp aired. To a A lesser extent-.the same require- "35 ment Ais imposed .on they manufacturesofnon'- thermost'atic disks. as localized vstresses in such disks meanearlywiailure in operation of that portion of th disk lunduly strained, and `thus\ shorter life of .the disks; taken on the-average. y

l'he method which has'now been found to be m st :advantageos comprises taking an initially the peripheral region gf the disk in such manner bottom out of the c up and then pressing the. corrugating sides st sa'id, cup into `final conformation fin a series'of die7pressed steps. In. this man ner,no great stress is introduced into any one bart 'orin .disk at any unie, but rather, the 5o' valuable overcentering element, while if the. ma# 20 lle thble hbwll 1n Marshall Patent 1,481i021, il mail Patent 1,700.17?, 01j? Bush Patent 1,870.-

20 'liie initial manufacturing the corruf gated disk bringing the' flat disk of lliig;l

1 tothe `forni shown inFizures and 4. fThis stepcomprises subjecting the peripheral region or thc risk i, indicated hy iri'uniciuii in Figures.,

toa sitable'dle-stamping action whereby said" region is bent slightly'v upward.l sivinsl tlm disk the generally of a shallow plate'.

inasmuch as-the outer periphery lci! the'pltite,

indicated .by numeral' 3, is less in total length 00 than the outer periphery of the disk I," this-shaping operation ls achieved initiating the forma.-

spaced, a corrugations l, it will be vseem vary from maximum depth at the periphery Itosubstantiallyserodepth at-a line 5 wherein they Join the central,` uncorrugated re; monitor-thc, disk. 'ii' It win bc understood that' line l represents a or short, straight 'rhirinitini'ctcp c: manufacture may hc cuit performed by properly Ashaped vmale and femalediss which are, in fact, the obverse and* step of manufacture comprises hrinsina thc itc mi s'condition toits Iig. Beonditlonffn corrugationst are veryshallow havingbarely been in rotin.- in thc rings .condition 5 0 thearugationss-aredistinctly marked. Inthe ccnditich. thc, inner1 cdg'ccci thc corruga- I, now indicated-by numerall. have. been j reverse prints or the disk I. in'its Fig; 3 condition. The

leotcncrcdcpthntthc ofiuntincswiththcportion` conformationot ih cccrrusaticnniccicatiyindicatcdinmm j i fwheretheuterperipheryotthedishindicatcd tionaliy 'cutting out the bot Suitable lthermostatic metilnished disk isto be a thrmostatic one,I

the maximum resilientgmetaLfor therm 2 '2,979,847 'inngricur'cc isndaiiiintntcin pian cndcicvnstep comprises blanking or otthecup'whichisrep-f; resented by `the unomted region 0 ofthe criginni'disx. signets indicates thc disk` i in such condition." The region-I is preierablycut 'l out so .that'the .line oi ctting as nearly-approximatesthe .fold linecl as ble. I! this step is carried out with suitable accuracy.. the disk] in its-l 1"ig. 8 condition is substantially allyorruachieved, thcncxq gated no uncorrugated'material being l0 left. f ",From' its -Fig. 8 condition. the remaining steps of manufacturing are substantially the same' as lthose shown'in the said Spencer-gstellt 2.0i'i1`,l553. 4 'll'l'xtit is to now corrugated, substantially.

cylindrical body ,iscplaced between vdies' and-so compressed'tliat the upper periphery.; thereof is slowly toldedinw'ardly'-- toward the center or .the cylindrical shape. by moreL and more closely compressing the corrugations l at the upper end l. At the same time'. it is desirable to limit thep outward expansion o! the bottom periphery, repre' sented by the former fold linevl.' This flattening operation, 'if it maybe so carried o until the shapeof the' desired nlshed disk il- 26 lustrated in Fig. 93s The lligrilV illustration shows a disk which ls notentirely ilat, that is, the' inner periphery is not in the saine plane as the outer periphery but is iii a plane sliglitly displaced therefrom.' sivinsth'c dista slightly conical so conformation. .This Slishtf ponical conformationis fessential i'orthe desired snap-acting charac- -tcristiccof the disk.l i

The die-pressing involved transforming the blank in its Fig. 8 condition the nnished disk 35 'of Fig. 9 may be'cairied 'outf with apparatus identical tofthat lshown in Figures B, 9 and 10 of' the aforesaid Spencer Patent'2,001,553. This dlefpressiig may be'done in any-numberpf steps suitable tc thc diskbeing formed. und thc shaping 4o characteristics ct thc mctai of Three steps, such as `shown in the aforesaid' Spencer Patent 2,001,553 havebeen found to sive excellent results without intrcducinssubcntiariocciiscd stressesintheresultingdisk. 45 Fig;l9,as -has been-indicated, .illustrates a completed disk; i It willbeseen Vthat the cbifrugations i l are positioned vin the desired radial conformation, and it will'be apparent that the diskhas the desiredslightlycoieal coniormation.' The .so ru'gations-ll vary from an depth at t centerpt the disk.J or its inner periphery. to a;

um depth `whichis practieallyiat the outer periphery. hlst p rovlilestha't`l nicunt or hc it simply.' t.' tic metal, is' coiv .y .tained 'in the centrainiovable region of tlietlisk,A whereitwilldothemostgoodj f 'ihcdisxunmtcdinm-ccnrcrmcicthc typed: disicniuctrstcd in thc arci-csaidpehcer c Patcn't massen. A 'morcprncticsi dick is that chown inthc cicrcnud t usarsi,

-conilning u oitheeentrst portion ot the diskto undergo snap-actionf'iu resnonsc'tccuitsbiciactunticn: 'nicrim-'sinybc .c rormcd on thc diskcrehc 158- mbodimenl t by merely pressing itbetwaen-suitable diescsuiias 70 those indicated in ng. sci ths afor'esaid'spe'ncerf Patent 1,895,591. P18. 11-v Wm Il l m section'- ci thc riccio dismhcwccinrlyhcnthcccmm- B tions vary-from maximum depthfaft the periphery ci tc'miniinuni tn-cf points where they Join the intentionally ilattened periphery l. Fig. 11 also indicates the conicity of the nnished disk, and in this respect it may be said to represent a cross section of interpreted as illustrative and not in a limiting E 5 I l. The method of manufacturingradially corrugated snap-acting disks comprising Preparing a blank in the form of a ilat circular disk, corrugating the peripheral regionl of said blank in such manner that the blank a cupis slightly displaced from the peripheral JOHND.

5 Fig. 9 as well. shape, cutting the bottom from said cup, and in- 5 Thronshout the drawings 0f this apnlieatiOn. wardly compressing the walls of said cup at one the erruatins have been indicated aS being end thereof until the blank assumes a disk conformed by sharp folds. In actual practice, such formation in which the central portion is slightsharp folds are not desired, and it is preferable 1y displaced from the peripheral portion. lo that the bends be as-rounded as is feasible to '2. 'I'he method of `manufacturing radially cor- 10 make them. However, in order to show -such rugate'd snap-acting disks comprising preparinl rounded folds. it Wellid have beenneeeSSa-l'y to una blank in thev form of a ilat circular disk, corduly complicate the drawings of this'application; rugating the peripheral region of said disk in henee. the sharp folds of the drawings are for ilsuch manner that it assumes ln. cup-shape, cutls lustrative purposes Only and the actual. Practical ting the uncorrugated bottom from said cup, and 16 disk formed in accordance with the present ininwardly compressing the corrugated sides cf vention should be provided with rounded, instead said up nt the end formed from the original Offhnl'p. folds. v l outer edge of the disk blank until the blank asf A Particular advantage of the present invensumes a disk conformation Ain which the central 20 tion over the embodiment of the aforesaid Spencer poi-tien is slightly dispineed from the peripherni 20 Patent 2,001,553, invention shown in Fig. l thereof, portion,

is that the corruation. is accomplished with dies 3. The method as set forth in claim l in which' instead of rollers; and further, that the initial the mitin] eerrugnting is performed in auch manblank i8 a S0116- disk rather i"han an nnnin. and ner that the corrugations vary from 25- hence vis more easily handled. Further, "the ,depth et the periphery ofthe bien); te gunsten. 26

presence of the central. 89nd portion of the disk tally-zero depth at the point where the said peherein indicated by reference numeral I. during ripheriii region joins the central region or the the initial corrugitting step, has a tendency to man1; Y minimize stresses and strains in the corrugations 4 The method g1 manufacturing radially nors0 as they are initially formed. 'Ihe reason for this mated enepenngmeke Bs eet gni-thin eienn 1, 30

tendency is abstruse and need not be dwelt uponV in vwhieh the individui enrrugntinns nre pmm this vvlieatifm. vided with s. substantially roundedtontour.

1n view of the above,v it will be seen that the 5, The method of manufacturing radially corseveral objects of the invention are achieved and rugated snap-acting disks which comprises pre- 35 other advantageous results attained. A 'paring e blank int form of e natuur. eomi- Y As many changes could be made in carrying gating said blank i such manner that it asent the above methods Without departins #rem sumes the conformation of a cup, removing the the scope of the invention, it is intended that bottom from saidv cup, and comprising the walls all matter contained in the above description or ,lof said cup inwardly until the blank assumes a 4o shown in the accompanying drawings -sheu be ,-l/iiiiiir conformation in which the central pai-tion l lPatent Nog. liarch 9. 1937.7"

" Jomiorotssrr.

v It is' hereby certified that error appears in the printed specification. of the abovenumbered patent requiring correction itsl foll'ows': Page 3,'5 ysecond column. line 38,#c1am I5, 'fonthe word comprising read comv f pressing; and that the said Letters Patent shouldhev read vwith this correction therein that Ather same may coi'iiciriii to 'the' record-,ofthe ,css'einftbe Patent'(Jf'i'zl'ce,i.I I signed iinq sgsieathis asthdey orii'sy, i. D'. 1937. I

points where they loin the intentionally flattened periphery l. Fig. 11 also indicates the conicity of the nnished disk, and in this respect it may be said to represent a cross section of As many changes could be made in carryingA out the above methods without departing from the scope or the invention, it is intended 'that all matter contained in the above description or 4o shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting I 5 I l. The method of manufacturingradialiy cor- /diskj conformation in which the rugated snap-acting disks comprising Preparing a blank in the form of a flat circular disk, corrugating the peripheral regionl of said blank in such manner that the blank assumes a cupgating said blank i such manner that it assumes the conformation of a cup, removing the bottom from saidv cup, and comprising the walls {ofsaidcupinwardlyuntiltheblankassumesa is slightly displaced from thc peripheral JOHND.

5 Fig. 9 as well. shape, cutting the bottom from said cup, and in- 5 Throughout the drawings 0f this aPPllCaOn, wardly compressing the walls of said cup at one the @1111881110118 have been Indicated aS being end thereof until the blank assumes a disk conformed by sharp folds. In actual practice, Such formation in which the central portion is slight- Sharp folds are not desired, and it is preferable ly displaced from the peripheral portion. lo that the bends be as-rounded as is feasible t0 2. 'I'he method of `manufacturing radially corl0 make them. However, in order to show -such rugate'd snap-acting disks comprising preparing rOUnded OIGS. it would have heenneeeSS-l'y to una blank in tlfiev form of a ilat circular disk, corduly complicate the drawings of this'application; rugating the peripheral region of said disk in henee, the sharp folds of the drawings are for ilsuch manner that it assumes lil. cup-shape, cutlo lustrative purposes Only and the actual, Dreef-leal ting the uncorrugated bottom from said cup, and 16 disk formed in accordance with the present ininwardly compressing the corrugated sides of vention should be provided with rounded, instead said up et the end formed from the original Offhnl'p. folds. v l outer edge of the disk blank until the blank asf A Particular advantage of the present invensumes a disk conformation Ain which the central 20 tion over the embodiment of the aforesaid Spencer pol-uen 15 slightly displeeed from the periphenl 20 Patent 2,001,553, invention shown in Fig. l thereof, portion,

is that the corruation. is accomplished with dies 3. The method as set forth in claim l in which instead 0f rollers: and further, that the initial the initial corrugating is perfumed in such manblank i8 a S0116- dlsk rather than an nnnlu. and ner that the corrugations vary from maximum 25- hence vis more easily handled. Further, "the ,depth et the periphery ofthe blank te em. 26

presence of the central, solid portion of the disk any zero depth at the point, where the 1d peherein indicated by reference numeral I. during "ripiierai region joins the central region or the the initial corrugating step, has a tendency to bien; Y minimize stresses and strains in the corrugations 4 The method of manufacturing radially eer- 80 as they are initially formed. 'Ihe reason for this mei-,ed snepeeungmeks es eet fel-thin claim 1, 30 tendency is abstruse and need not be dwelt uponV n vwhieh the individuel eerrugguens e pm. 1n this applicatif@ vided with s. substantially roundedcontour.

1n view of the above,v it will be seen that the 5, The method of manufacturing radially oorseveral objects of the invention are achieved and mated harming disks which www We- 35 other advantageous results attained. 'paring a blank int form of a sandisk. comicentralini-sioni lPatent Nog. liarch 9. 1937;"

" Jolisasotssn.

v It is hereby certified that error appears inl the printed specification. of the abovenumbered patent requiring correction asl foll'ows': Page 3,'5 ysecond column. line 38,#c1aim ,5, 'forxthe word comprising read coiil-v f pressing; and that the said Letters Patent shouldbe read vwith this correction therein that Ather same may coi'lifo'riii' to 'the' record-,ofthe ,cas'elinfthe'5 Patent'(Jf'i'zl'ce.i.I I signed and spiedini@ astlid'ay orli'ay, il. D'. 19:57.` I 

